Comment 4. Case 26 had a cervical spine process fracture which is AIS 2 and flail chest which is AIS 4, hence this patient's ISS is 24 but in error this was printed as 25, again this does not influence the probability of survival or outcome for this patient.
The use of level of consciousness has a definite role in AIS 80, in fact the AIS 80 suggests that in cases where information on both anatomical lesion and level of consciousness is available the higher of the two AIS codes should be assigned to the
injury. The study was based on experience of one General District Hospital and the cases were accurately reported. In this study only one patient's score was incorrect, Case 13, where the outcome may have been affected and hence we would disagree that there are any fundamental flaws in the study. We think Mr Cross and his colleagues are working out the injury severity score from AIS 90 which has only recently been published and hence the confusion. As mentioned earlier, this study was based on AIS 80, this may explain some of their concerns regarding the study. We are informed from the MTOS (UK) Office that both they and MTOS (USA) do not recommend the use of AIS 90 for a study like this, ie TRISS methodology, at present, as AIS 90 requires different coefficients to work out the probability of survival, and we hope that Mr Cross and his colleagues at HEMS are not using AIS 90 for analysis of their results. NADEEM NAYEEM FRCS Senior Registrar in Accident and Emergency Guy's Hospital London MOHINDRA B KOTECHA FRCS Consultant in Accident & Emergency Medicine Luton and Dunstable Hospital Luton
Laparoscopic cholecystectomy We welcome the comments of Lord McColl on laparoscopic cholecystectomy (Annals, July 1992, vol 74, p231), pointing out that the risk of accidental bowel perforation can be greatly reduced by the 'open' technique of laparoscopy in which the abdomen is entered under direct vision (1). He failed to mention, however, that the open technique should also completely eliminate the most feared complication of laparoscopy, that is major vessel injury (2). This catastrophic event is estimated to occur in between 3 and 10 per 10 000 closed laparoscopic procedures (3-5), but these retrospective surveys may underestimate the incidence. We are aware of major vessel injuries occurring during diagnostic laparoscopy and laparoscopic cholecystectomy using both reusable and disposable trocars with a safety shield. The open technique also avoids the risk of subcutaneous, omental, or mesenteric emphysema from insufflation through a misplaced Veress needle. Unfortunately, few surgeons choose to adopt the open technique of laparoscopy. The trocar can be placed anywhere in the abdomen and does not add time to the procedure once the surgeon has become familiar with the technique. The use of a Hasson's laparoscopic cannula, with its olive-shaped sleeve on the shaft of the cannula, greatly simplifies the technique. Moreover, reusable trocars can be safely used in open laparoscopy, resulting in a significant saving for those who use disposable trocars. ANDREW J MCMAHON FRCS Surgical Research Fellow PATRICK J O'DWYER MCh FRCS Senior Lecturer in Surgery
439
JOHN N BAXTER MD FRACS Senior Lecturer in Surgery
University Department of Surgery Western Infirmary, Glasgow References I Penfield AJ. How to prevent complications of open laparoscopy. J Reprod Med 1985;30:660. 2 Baadsgaard SE, Billek S, Egeblad K. Major vascular injury during gynecologic laparoscopy. Acta Obstet Gynecol Scand 1989;68:283-5. 3 Mintz M. Risks and prophylaxis in laparoscopy: a survey of 100,000 cases. J Reprod Med 1977;18:269-72. 4 Peterson H, Greenspan J, Ory H. Death following puncture of the aorta during laparoscopic sterilization. Obstet Gynecol 1981;59: 133-4. S Riedel HH, Willenbrock-Lehnmann E, Mecke H, Semm K. The frequency of distribution of various pelviscopic (laparoscopic) operations, including complication rates-statistics of the Federal Republic of Germany in the years 1983-1985. Zentralbl Gynakol 1989;11l:78-91.
Can cholangiography be safely abandoned in laparoscopic cholecystectomy? Laparoscopic operative cholangiography: a simple, successful, cost-effective method The first definite warning that laparoscopic cholecystectomy may lead to an increase in damage to the major bile ducts came from a group of American Surgeons (1) who found a damage rate of 0.5% in just over 1500 patients. This compares with a rate of 0.15% found in open cholecystectomy (2). At a recent Congress in Bordeaux (3), the incidence of major duct injury in several large series was reported; in just over 8000 patients in Baltimore it was 0.22%, the Swiss Association found in just over 1000 patients and a Belgium Group in just over 3000 patients a rate of 0.5%; in a series from Japan of nearly 3000 patients the rate was 0.9% and in a series of 1100 patients from Singapore the rate was 1.6%. There were reports from South Carolina and the Lahey Clinic describing 26 patients who had suffered major duct injury during laparoscopic cholecystectomy. Only one of these patients had had operative cholangiography which led to the immediate recognition of the injury; approximately 50% of the remaining patients had a delayed diagnosis. I was therefore interested in your recent articles (Annals, July 1992 vol 74, p248, p252) which used one reference in each case case to suggest that operative cholangiography did or did not decrease the risk of main duct damage. The authors of those papers know that there is not enough information from the literature to give us the answer to this question. In the absence of that answer, the rule in order to avoid damage is to know at operation the precise position of the bile ducts, particularly the confluence of the common hepatic duct, the cystic duct and the common bile duct. The confluence can be identified by direct vision as in open surgery, endoscopic vision which is only possible in a small minority of cases, or by X-ray vision (peroperative cholangiography via the cystic duct or gallbladder). If the confluence cannot be identified by the latter two methods then conversion to an open operation should follow. I am concerned about the approach of tracing the cystic duct from the gallbladder and not visualising the confluence. This approach can be difficult technically because of bleeding problems; more importantly, the cystic duct may be absent and the gallbladder open directly into the right hepatic or common
440
Comment
bile duct. Perhaps the preoperative demonstration of the anatomy by IVC or ERCP may prevent difficulties in these cases. Operative cholangiography is also of value to demonstrate ductal damage and allow immediate repair. It also encourages emptying of the cystic duct of any small stones or debris. Operative cholangiography has its problems; it is theatre time and technology consuming, it may damage a short cystic duct making clipping difficult and it has a failure rate of 5-50%. This failure rate will become minimal if practised frequently. It is important to know that major bile duct damage leads to considerable morbidity and the mortality may reach 8% (4). It should therefore be obligatory for all cholecystectomists, open or endoscopic, to identify the confluence of the ducts before finally dividing any ductal structure. It would seem wise until further information becomes available to continue using operative cholangiography in all cases unless there is a very strong reason not to. G H DICKSON MS FRCS Consultant Surgeon Worthing and Southlands Hospitals West Sussex
References I The Southern Surgeons Club. A prospective analysis of 1518 laparoscopic cholecystectomies. N Engl J Med 1991;324: 1073-8. 2 Raute M, Schaup W. Iatrogenic damage of the bile ducts caused by cholecystectomy. Langenbecks Arch Chir 1988;373:
345-54. 3 3rd World Congress of Endoscopic Surgery, Bordeaux 1992, Abstracts Nos. 678, 149, 782, 780, 781, 561, 101. 4 McSherry CK, Glenn. The incidences and causes of death following surgery for non-malignant biliary tract disease. Ann Surg 1980;191:271-5. The recent paper by Gillams et al. (Annals, July 1992, vol 74, p248) addresses one of the most important issues in laparoscopic cholecystectomy. Their results show that preoperative ultrasonography will identify a large proportion of patients with stones in the common bile duct. These stones can then be dealt with endoscopically before surgery. What the paper fails to address is whether an operative cholangiogram will reduce the risk of serious ductal injury by providing a 'road map' of Calot's triangle. The paper they refer to when they state that the bile duct is often injured before cholangiography dealt with open cholecystectomy. This difference is crucial as the common bile duct is not always visualised at laparoscopic cholecystectomy and the cholangiogram may provide the only indication of the proximity of the cystic duct (marked by the holding clip) to the common duct (1). This is an important question and is given added weight by recent reports from the USA of ductal injury at laparoscopic cholecystectomy. For example, Stewart and Way recently reported their experience in a referral centre of 16 patients with bile duct injuries after laparoscopic cholecystectomy (2). The duct injury in five of these patients was from clip application to the common bile duct to control bleeding-not a common problem at the open procedure. At the very least it should be apparent that the question of the role of operative cholangiography at laparoscopic cholecystectomy is unanswered. Given this situation it seems unwise to disregard the guidelines for safe removal of the gallbladder evolved over many years of open biliary surgery (3).
One eventual compromise may be the development of a policy of selective cholangiography based on the assessment of risk factors as described by Montariol et al. (4). Given that there are no controlled studies comparing the incidence of ductal injury at laparoscopic cholecystectomy with or without operative cholangiography, the answer to the question posed by the authors in their title must remain 'do not know'. References I Cuschieri A. Berci G. Laparoscopic Biliary Surgery. Oxford: Blackwell, 1990:73-82. 2 Stewart L, Way LW. Bile duct injuries during laparoscopic cholecystectomy. The Society for Surgery of the Alimentary Tract, Program of the 33rd Meeting, 1992: 598A (Abstract). 3 Gunn AA. Cholecystectomy and cholecystostomy. In: Dudley HAF ed. Atlas of Operative Surgery. London: Butterworths, 1981:306-27. 4 Montariol T, Marre P, Julienne P, Bataille B. Safety of laparoscopic cholecystectomy performed without operative cholangiography. Br J Surg 1992;79(Supplement): S10. AJITH SIRIWARDENA MD FRCS Senior Registrar in General Surgery North Manchester General Hospital Manchester
Laparoscopic operative cholangiography: a simple, successful, cost-effective method We read with interest the technique of Fligelstone et al. for laparoscopic operative cholangiography (Annals, July 1992, vol 74, p252). We have'attempted a similar technique using a size 6G Chevaseau.ureteric catheter to cannulate the cystic duct with a Medicut® needle to puncture the anterior wall. We encountered several problems. This method requires coordination between two operators. Cannulation of the cystic duct often required several attempts due to the natural recoil of the catheter, often resulting in a crushed or deformed catheter which was functionally useless. This occurred despite the presence of a stilette which seemed to offer little protection. In addition, when applying a clip across the cystic wall, the margin between complete catheter occlusion and achieving a secure position was small. Our preference is to use an Olson clamp with a size 6G Chevaseau catheter. The clamp consists of a hollow lightweight aluminium cylinder approximately 30 cm long with a calibre which fits a 5 mm port snugly. The distal end of the clamp consists of a pair of opposing U-shaped jaws parallel to the long axis of the instrument which are controlled using a finely graduated ratchet mechanism in the handle of the clamp. The gallbladder is put on stretch superiorly and laterally using the midclavicular and midline port thus aligning the cystic duct with the clamp, which is introduced through the midaxillary port and advanced to the site of the incision in the cystic duct. The catheter with the stilette in situ is inserted and advanced down the clamp until it appears between the open jaws of the instrument. The cystic duct is cannulated and the clamp advanced over the catheter to a position allowing approximation of the jaws over both the cystic duct and the catheter within it. If need be, the clamp can be released gently allowing the catheter to be advanced or withdrawn within the cystic duct without fear of inadvertent extubation. Once in position, the stilette can be withdrawn and a 20 ml syringe of normal saline connected using a rubber seal. Aspiration of bile excludes air and confirms catheter patency. This technique has been attempted on 31 consecutive occasions with uniform success. We believe the stilette provides a useful degree of catheter
The use of level of consciousness has a definite role in AIS 80, in fact the AIS 80 suggests that in cases where information on both anatomical lesion and level of consciousness is available the higher of the two AIS codes should be assigned to the
injury. The study was based on experience of one General District Hospital and the cases were accurately reported. In this study only one patient's score was incorrect, Case 13, where the outcome may have been affected and hence we would disagree that there are any fundamental flaws in the study. We think Mr Cross and his colleagues are working out the injury severity score from AIS 90 which has only recently been published and hence the confusion. As mentioned earlier, this study was based on AIS 80, this may explain some of their concerns regarding the study. We are informed from the MTOS (UK) Office that both they and MTOS (USA) do not recommend the use of AIS 90 for a study like this, ie TRISS methodology, at present, as AIS 90 requires different coefficients to work out the probability of survival, and we hope that Mr Cross and his colleagues at HEMS are not using AIS 90 for analysis of their results. NADEEM NAYEEM FRCS Senior Registrar in Accident and Emergency Guy's Hospital London MOHINDRA B KOTECHA FRCS Consultant in Accident & Emergency Medicine Luton and Dunstable Hospital Luton
Laparoscopic cholecystectomy We welcome the comments of Lord McColl on laparoscopic cholecystectomy (Annals, July 1992, vol 74, p231), pointing out that the risk of accidental bowel perforation can be greatly reduced by the 'open' technique of laparoscopy in which the abdomen is entered under direct vision (1). He failed to mention, however, that the open technique should also completely eliminate the most feared complication of laparoscopy, that is major vessel injury (2). This catastrophic event is estimated to occur in between 3 and 10 per 10 000 closed laparoscopic procedures (3-5), but these retrospective surveys may underestimate the incidence. We are aware of major vessel injuries occurring during diagnostic laparoscopy and laparoscopic cholecystectomy using both reusable and disposable trocars with a safety shield. The open technique also avoids the risk of subcutaneous, omental, or mesenteric emphysema from insufflation through a misplaced Veress needle. Unfortunately, few surgeons choose to adopt the open technique of laparoscopy. The trocar can be placed anywhere in the abdomen and does not add time to the procedure once the surgeon has become familiar with the technique. The use of a Hasson's laparoscopic cannula, with its olive-shaped sleeve on the shaft of the cannula, greatly simplifies the technique. Moreover, reusable trocars can be safely used in open laparoscopy, resulting in a significant saving for those who use disposable trocars. ANDREW J MCMAHON FRCS Surgical Research Fellow PATRICK J O'DWYER MCh FRCS Senior Lecturer in Surgery
439
JOHN N BAXTER MD FRACS Senior Lecturer in Surgery
University Department of Surgery Western Infirmary, Glasgow References I Penfield AJ. How to prevent complications of open laparoscopy. J Reprod Med 1985;30:660. 2 Baadsgaard SE, Billek S, Egeblad K. Major vascular injury during gynecologic laparoscopy. Acta Obstet Gynecol Scand 1989;68:283-5. 3 Mintz M. Risks and prophylaxis in laparoscopy: a survey of 100,000 cases. J Reprod Med 1977;18:269-72. 4 Peterson H, Greenspan J, Ory H. Death following puncture of the aorta during laparoscopic sterilization. Obstet Gynecol 1981;59: 133-4. S Riedel HH, Willenbrock-Lehnmann E, Mecke H, Semm K. The frequency of distribution of various pelviscopic (laparoscopic) operations, including complication rates-statistics of the Federal Republic of Germany in the years 1983-1985. Zentralbl Gynakol 1989;11l:78-91.
Can cholangiography be safely abandoned in laparoscopic cholecystectomy? Laparoscopic operative cholangiography: a simple, successful, cost-effective method The first definite warning that laparoscopic cholecystectomy may lead to an increase in damage to the major bile ducts came from a group of American Surgeons (1) who found a damage rate of 0.5% in just over 1500 patients. This compares with a rate of 0.15% found in open cholecystectomy (2). At a recent Congress in Bordeaux (3), the incidence of major duct injury in several large series was reported; in just over 8000 patients in Baltimore it was 0.22%, the Swiss Association found in just over 1000 patients and a Belgium Group in just over 3000 patients a rate of 0.5%; in a series from Japan of nearly 3000 patients the rate was 0.9% and in a series of 1100 patients from Singapore the rate was 1.6%. There were reports from South Carolina and the Lahey Clinic describing 26 patients who had suffered major duct injury during laparoscopic cholecystectomy. Only one of these patients had had operative cholangiography which led to the immediate recognition of the injury; approximately 50% of the remaining patients had a delayed diagnosis. I was therefore interested in your recent articles (Annals, July 1992 vol 74, p248, p252) which used one reference in each case case to suggest that operative cholangiography did or did not decrease the risk of main duct damage. The authors of those papers know that there is not enough information from the literature to give us the answer to this question. In the absence of that answer, the rule in order to avoid damage is to know at operation the precise position of the bile ducts, particularly the confluence of the common hepatic duct, the cystic duct and the common bile duct. The confluence can be identified by direct vision as in open surgery, endoscopic vision which is only possible in a small minority of cases, or by X-ray vision (peroperative cholangiography via the cystic duct or gallbladder). If the confluence cannot be identified by the latter two methods then conversion to an open operation should follow. I am concerned about the approach of tracing the cystic duct from the gallbladder and not visualising the confluence. This approach can be difficult technically because of bleeding problems; more importantly, the cystic duct may be absent and the gallbladder open directly into the right hepatic or common
440
Comment
bile duct. Perhaps the preoperative demonstration of the anatomy by IVC or ERCP may prevent difficulties in these cases. Operative cholangiography is also of value to demonstrate ductal damage and allow immediate repair. It also encourages emptying of the cystic duct of any small stones or debris. Operative cholangiography has its problems; it is theatre time and technology consuming, it may damage a short cystic duct making clipping difficult and it has a failure rate of 5-50%. This failure rate will become minimal if practised frequently. It is important to know that major bile duct damage leads to considerable morbidity and the mortality may reach 8% (4). It should therefore be obligatory for all cholecystectomists, open or endoscopic, to identify the confluence of the ducts before finally dividing any ductal structure. It would seem wise until further information becomes available to continue using operative cholangiography in all cases unless there is a very strong reason not to. G H DICKSON MS FRCS Consultant Surgeon Worthing and Southlands Hospitals West Sussex
References I The Southern Surgeons Club. A prospective analysis of 1518 laparoscopic cholecystectomies. N Engl J Med 1991;324: 1073-8. 2 Raute M, Schaup W. Iatrogenic damage of the bile ducts caused by cholecystectomy. Langenbecks Arch Chir 1988;373:
345-54. 3 3rd World Congress of Endoscopic Surgery, Bordeaux 1992, Abstracts Nos. 678, 149, 782, 780, 781, 561, 101. 4 McSherry CK, Glenn. The incidences and causes of death following surgery for non-malignant biliary tract disease. Ann Surg 1980;191:271-5. The recent paper by Gillams et al. (Annals, July 1992, vol 74, p248) addresses one of the most important issues in laparoscopic cholecystectomy. Their results show that preoperative ultrasonography will identify a large proportion of patients with stones in the common bile duct. These stones can then be dealt with endoscopically before surgery. What the paper fails to address is whether an operative cholangiogram will reduce the risk of serious ductal injury by providing a 'road map' of Calot's triangle. The paper they refer to when they state that the bile duct is often injured before cholangiography dealt with open cholecystectomy. This difference is crucial as the common bile duct is not always visualised at laparoscopic cholecystectomy and the cholangiogram may provide the only indication of the proximity of the cystic duct (marked by the holding clip) to the common duct (1). This is an important question and is given added weight by recent reports from the USA of ductal injury at laparoscopic cholecystectomy. For example, Stewart and Way recently reported their experience in a referral centre of 16 patients with bile duct injuries after laparoscopic cholecystectomy (2). The duct injury in five of these patients was from clip application to the common bile duct to control bleeding-not a common problem at the open procedure. At the very least it should be apparent that the question of the role of operative cholangiography at laparoscopic cholecystectomy is unanswered. Given this situation it seems unwise to disregard the guidelines for safe removal of the gallbladder evolved over many years of open biliary surgery (3).
One eventual compromise may be the development of a policy of selective cholangiography based on the assessment of risk factors as described by Montariol et al. (4). Given that there are no controlled studies comparing the incidence of ductal injury at laparoscopic cholecystectomy with or without operative cholangiography, the answer to the question posed by the authors in their title must remain 'do not know'. References I Cuschieri A. Berci G. Laparoscopic Biliary Surgery. Oxford: Blackwell, 1990:73-82. 2 Stewart L, Way LW. Bile duct injuries during laparoscopic cholecystectomy. The Society for Surgery of the Alimentary Tract, Program of the 33rd Meeting, 1992: 598A (Abstract). 3 Gunn AA. Cholecystectomy and cholecystostomy. In: Dudley HAF ed. Atlas of Operative Surgery. London: Butterworths, 1981:306-27. 4 Montariol T, Marre P, Julienne P, Bataille B. Safety of laparoscopic cholecystectomy performed without operative cholangiography. Br J Surg 1992;79(Supplement): S10. AJITH SIRIWARDENA MD FRCS Senior Registrar in General Surgery North Manchester General Hospital Manchester
Laparoscopic operative cholangiography: a simple, successful, cost-effective method We read with interest the technique of Fligelstone et al. for laparoscopic operative cholangiography (Annals, July 1992, vol 74, p252). We have'attempted a similar technique using a size 6G Chevaseau.ureteric catheter to cannulate the cystic duct with a Medicut® needle to puncture the anterior wall. We encountered several problems. This method requires coordination between two operators. Cannulation of the cystic duct often required several attempts due to the natural recoil of the catheter, often resulting in a crushed or deformed catheter which was functionally useless. This occurred despite the presence of a stilette which seemed to offer little protection. In addition, when applying a clip across the cystic wall, the margin between complete catheter occlusion and achieving a secure position was small. Our preference is to use an Olson clamp with a size 6G Chevaseau catheter. The clamp consists of a hollow lightweight aluminium cylinder approximately 30 cm long with a calibre which fits a 5 mm port snugly. The distal end of the clamp consists of a pair of opposing U-shaped jaws parallel to the long axis of the instrument which are controlled using a finely graduated ratchet mechanism in the handle of the clamp. The gallbladder is put on stretch superiorly and laterally using the midclavicular and midline port thus aligning the cystic duct with the clamp, which is introduced through the midaxillary port and advanced to the site of the incision in the cystic duct. The catheter with the stilette in situ is inserted and advanced down the clamp until it appears between the open jaws of the instrument. The cystic duct is cannulated and the clamp advanced over the catheter to a position allowing approximation of the jaws over both the cystic duct and the catheter within it. If need be, the clamp can be released gently allowing the catheter to be advanced or withdrawn within the cystic duct without fear of inadvertent extubation. Once in position, the stilette can be withdrawn and a 20 ml syringe of normal saline connected using a rubber seal. Aspiration of bile excludes air and confirms catheter patency. This technique has been attempted on 31 consecutive occasions with uniform success. We believe the stilette provides a useful degree of catheter
